Thursday, January 5, 2012

Your hamstring muscles play an important role in keeping your knees, pelvis and spine in alignment. But sitting all day can cause hamstrings to become weak and ineffective. You don't need a gym membership or expensive equipment to restore tone and definition to your hamstrings. Doing dips on a stability ball is a challenging and effective way to strengthen your hamstring muscles.

Hamstring Anatomy and Function

Located at the back of your upper thigh, the hamstrings are a group of three muscles: the semitendinosus, the semimembranosus and the biceps femoris. The hamstrings perform the dual function of flexing the knee and extending the hip. Hamstring muscles also play an important role in stabilizing the knee joint. To effectively work the hamstrings using a stability ball, select a ball that, when firmly inflated, allows you to sit on it with both your knees and hips at 90 degrees.

Basic Hamstring Dips

Lie on your back with your hands palms-down at your sides. Plant the soles of your feet hip-width apart near the top of the ball, with your knees bent at 90 degrees. Exhale and press your heels into the ball, lifting your hips toward the ceiling until you form a straight line from your knees to your shoulder blades. Inhale and slowly lower your hips, dipping toward the floor but not resting. Exhale and thrust your hips upward again. Repeat as many times as you can with control and good form.

Single-Leg Dips

To make your dips more challenging, rest the ankle of one foot just above the knee of the opposite leg, rotating your hip outward so your knee points to the side. Plant the sole of the opposite foot near the top of the ball, with your knee bent at 90 degrees and your hands palms-down at your sides. Exhale and push off with your heel, thrusting your hips upward until they are fully extended. Inhale and lower, dipping toward the floor.

Rolling Leg Curl

To work your hamstring as both a hip extensor and a knee flexor, lie on your back and rest your heels hip-width at the top of your ball with your knees straight. Push downward with your heels, and lift your hips off the floor, forming a straight line from heels to shoulder blades. Exhale and bend your knees, allowing the ball to roll toward you as you draw your knees toward your hips. Inhale and straighten your knees, rolling the ball away from you. Repeat as many times as you can with control and good form.